METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

• US 20120231580A1
• Filed: 03/07/2012
• Published: 09/13/2012
• Est. Priority Date: 03/11/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei, SATO, Yuhei, SATO, Keiji, MARUYAMA, Tetsunori, KOEZUKA, Junichi
• Granted Patent: US 8,828,794 B2
• Time in Patent Office: Days
• US Class Current: 438/104
• CPC Class Codes: H01L 21/02175 characterised by the metal H01L21/02197 takes precedence
• CPC Class Codes: H01L 21/02252 formation by plasma treatment, e.g. plasma oxidation of the substrate after treatment of an insulating film by plasma H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02636 Selective deposition, e.g. simultaneous growth of mono- and non-monocrystalline semiconductor materials
• CPC Class Codes: H01L 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H01L 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence
• CPC Class Codes: H01L 21/383 using diffusion into or out of a solid from or into a gaseous phase
• CPC Class Codes: H01L 21/40 Alloying of impurity materials, e.g. doping materials, electrode materials, with a semiconductor body
• CPC Class Codes: H01L 21/477 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/38 - H01L21/449 and H01L21/461 - H01L21/475 take precedence
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

In a manufacturing process of a transistor including an oxide semiconductor film, oxygen doping treatment is performed on the oxide semiconductor film, and then heat treatment is performed on the oxide semiconductor film and an aluminum oxide film provided over the oxide semiconductor film. Consequently, an oxide semiconductor film which includes a region containing more oxygen than a stoichiometric composition is formed. The transistor formed using the oxide semiconductor film can have high reliability because the amount of change in the threshold voltage of the transistor by a bias-temperature stress test (BT test) is reduced.

Claims

1. A method of manufacturing a semiconductor device, the method comprising the steps of:

forming an oxide film;

forming an oxide semiconductor film on the oxide film;

forming an aluminum oxide film over the oxide semiconductor film so that the aluminum oxide film is in contact with part of the oxide semiconductor film; and

performing heat treatment on the oxide semiconductor film and the aluminum oxide film.

2. The method of manufacturing a semiconductor device according to claim 1, wherein the oxide film is a silicon oxide film.

3. The method of manufacturing a semiconductor device according to claim 1, wherein the oxide semiconductor film comprises indium, gallium, and zinc.

4. The method of manufacturing a semiconductor device according to claim 1, wherein the heat treatment is performed at a temperature of higher than or equal to 350°

C. and lower than or equal to 650°

C.

5. The method of manufacturing a semiconductor device according to claim 1, wherein the oxide film and the oxide semiconductor film are successively formed without exposure to air.

6. The method of manufacturing a semiconductor device according to claim 1, wherein the oxide semiconductor film comprises a crystalline region.

7. A method of manufacturing a semiconductor device, the method comprising the steps of:

forming an oxide film;

forming an oxide semiconductor film on the oxide film;

forming an aluminum oxide film over the oxide semiconductor film so that the aluminum oxide film is in contact with part of the oxide semiconductor film;

adding oxygen into the oxide semiconductor film so that a region of the oxide semiconductor film comprises more oxygen than a stoichiometric composition; and

performing heat treatment on the oxide semiconductor film and the aluminum oxide film after adding the oxygen.

8. The method of manufacturing a semiconductor device according to claim 7, wherein the oxide film is a silicon oxide film.

9. The method of manufacturing a semiconductor device according to claim 7, wherein the oxide semiconductor film comprises indium, gallium, and zinc.

10. The method of manufacturing a semiconductor device according to claim 7, wherein the heat treatment is performed at a temperature of higher than or equal to 350°

C. and lower than or equal to 650°

C.

11. The method of manufacturing a semiconductor device according to claim 7, wherein the oxide film and the oxide semiconductor film are successively formed without exposure to air.

12. The method of manufacturing a semiconductor device according to claim 7, wherein a peak of a concentration of oxygen in the oxide semiconductor film into which the oxygen is added is higher than or equal to 1×

10¹⁸/cm³ and lower than or equal to 3×

10²¹/cm³.

13. The method of manufacturing a semiconductor device according to claim 7, wherein the oxide semiconductor film comprises a crystalline region.

14. A method of manufacturing a semiconductor device, the method comprising the steps of:

forming an oxide film;

forming an oxide semiconductor film on the oxide film;

performing first heat treatment on the oxide semiconductor film to remove a hydrogen atom from the oxide semiconductor film;

forming an aluminum oxide film over the oxide semiconductor film after performing the first heat treatment so that the aluminum oxide film is in contact with part of the oxide semiconductor film;

adding oxygen into the oxide semiconductor film after performing the first heat treatment so that a region of the oxide semiconductor film comprises more oxygen than a stoichiometric composition; and

performing second heat treatment on the oxide semiconductor film and the aluminum oxide film after adding the oxygen.

15. The method of manufacturing a semiconductor device according to claim 14, wherein the oxide film is a silicon oxide film.

16. The method of manufacturing a semiconductor device according to claim 14, wherein the oxide semiconductor film comprises indium, gallium, and zinc.

17. The method of manufacturing a semiconductor device according to claim 14, wherein the first heat treatment is performed at a temperature of higher than or equal to 250°

C. and lower than or equal to 700°

C.

18. The method of manufacturing a semiconductor device according to claim 14, wherein the second heat treatment is performed at a temperature of higher than or equal to 350°

C. and lower than or equal to 650°

C.

19. The method of manufacturing a semiconductor device according to claim 14, wherein the oxide film and the oxide semiconductor film are successively formed without exposure to air.

20. The method of manufacturing a semiconductor device according to claim 14, wherein a peak of a concentration of oxygen in the oxide semiconductor film into which the oxygen is added is higher than or equal to 1×

10¹⁸/cm³ and lower than or equal to 3×

10²¹/cm³.

21. The method of manufacturing a semiconductor device according to claim 14, wherein the oxide semiconductor film comprises a crystalline region.